Combination for electrolytic reduction of alumina

Patent · Tue Apr 30 00:00:00 EDT 2002

OSTI ID:874384

Brown, Craig W ^[1]; Brooks, Richard J ^[1]; Frizzle, Patrick B ^[2]; Juric, Drago D ^[3]

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1. Seattle, WA
2. Lynnwood, WA
3. Bulleen, AU

An electrolytic bath for use during the electrolytic reduction of alumina to aluminum. The bath comprises molten electrolyte having the following ingredients: AlF.sub.3 and at least one salt selected from the group consisting of NaF, KF, and LiF; and about 0.004 wt. % to about 0.2 wt. %, based on total weight of the molten electrolyte, of at least one transition metal or at least one compound of the metal or both. The compound is, a fluoride; oxide, or carbonate. The metal is nickel, iron, copper, cobalt, or molybdenum. The bath is employed in a combination including a vessel for containing the bath and at least one non-consumable anode and at least one dimensionally stable cathode in the bath. Employing the instant bath during electrolytic reduction of alumina to aluminum improves the wetting of aluminum on a cathode by reducing or eliminating the formation of non-metallic deposits on the cathode.

• Research Organization: Pacific Northwest National Laboratory (PNNL), Richland, WA (United States)
• DOE Contract Number: 310468-A-UF
• Assignee: Northwest Aluminum Technology (The Dalles, OR)
• Patent Number(s): US 6379512
• Application Number: 09/721,846
• OSTI ID: 874384
• Country of Publication: United States
• Language: English

Related Subjects

combination
electrolytic
reduction
alumina
bath
aluminum
molten
electrolyte
following
ingredients
alfsub3
salt
selected
consisting
naf
kf
lif
0004
wt
02
based
total
weight
transition
metal
compound
fluoride
oxide
carbonate
nickel
iron
copper
cobalt
molybdenum
employed
including
vessel
containing
non-consumable
anode
dimensionally
stable
cathode
employing
instant
improves
wetting
reducing
eliminating
formation
non-metallic
deposits
transition metal
electrolytic reduction
electrolytic bath
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